A Washington, D.C. policy bans ads with religious messages from public transit. Is that constitutional? Supreme Court precedent says yes and no.

Like many writers, I spend a great deal of time staring out my office window. This has made me a connoisseur of the advertisements that grace the sides of the Washington, D.C., buses that stop across the street on their journey down Connecticut Avenue. Lately, I’ve seen a lot for Metro PCS, the prepaid wireless service, and for C-SPAN (“Where history unfolds daily”). My favorite recent ad campaign is the one for Georgetown basketball. On the assumption, apparently, that people go to college hoops games to watch the head coach, it declares, “PATRICK. EWING. IS. BACK.”

What I don’t see are ads for church. That’s because Washington Metropolitan Area Transit Authority (WMATA, pronounced “wuh-motta”) policy doesn’t allow ad space to be used for religious messages.

The Catholic Church’s Archdiocese of Washington is suing to overturn that policy. It wanted to run a Christmas-season ad urging viewers to “Find the perfect gift.” The text was superimposed over a starry night sky, with silhouettes of shepherds and sheep evoking Bethlehem and Christ’s birth. If you visited findtheperfectgift.org, prominently featured on the banner, you’d discover that the perfect gift is Jesus.

An innocuous message, and one that would have been fine even a few years ago. But WMATA changed its rules for bus and metro advertising in 2015 to prohibit ads that promote or oppose religion, as well any campaign- or issue-related ads. D.C. is one of a growing number of cities, including New York, to adopt — and be sued over — this kind of policy. What’s ultimately at stake is whether cities must choose between accepting any and all paid messages — including offensive or otherwise questionable ones — or get out of the ad-sales business entirely, and sacrifice the revenue it generates.

If it bothers you that a city would ban church advertisements on the subway, you can direct your frustration toward the anti-Islamic provocateur Pam Geller. She is the co-founder of the nonprofit American Freedom Defense Initiative, which specializes in paranoid rants against “capitulation to the global jihad and Islamic supremacism, the ever-encroaching and unconstitutional power of the federal government, and the rapidly moving attempts to impose socialism and Marxism upon the American people.” The AFDI has sponsored ad campaigns around the country that test the limits of public tolerance for allowing advocacy on public transit. In San Francisco and New York, for example, the group has put up posters reading, “In any war between the civilized man and the savage, support the civilized man. Support Israel. Defeat Jihad.”

Messages like Geller’s put transit authorities in a tough spot. Under the First Amendment, once the government opens up a platform for private citizens’ speech, it can’t pick and choose which messages are okay and which aren’t. But there is a way out of this predicament. A transit system isn’t required to make itself an extension of the public square, according to the Supreme Court’s ruling in a 1974 case, Lehman v. City of Shaker Heights. A metro bus doesn’t count as a “public forum” — a category of places, like public parks, in which First Amendment protections are at their highest. Even when a bus is a forum of some kind, it’s a “limited public forum,” meaning a space that the government has opened up only to certain categories of communication.

The key attribute of a limited public forum is that, while the government still isn’t allowed to discriminate against speech presenting a certain viewpoint, it is allowed to discriminate based on subject matter — what the speech is about. It can take entire topics off the table, as long as it does so in a reasonable way that doesn’t favor one viewpoint over another. That’s why some systems, like those in New York and D.C., have responded to ads like Pam Geller’s by banning political and religious messages entirely. Call it the “this is why we can’t have nice things” approach: The only way to keep messages like Geller’s off their trains and buses is to ban entire categories of speech.

There is no theoretically consistent way to police the difference between 'viewpoint' and 'topic.'

At first glance, the law seems to be on WMATA’s side: The policy bans all religious messages, pro or con, so it’s a “subject-matter” restriction. But the church disagrees. Its lawyers argue that the rule is actually viewpoint discrimination. The “Perfect Gift” website offers links to Catholic Mass schedules, suggestions for how to celebrate Christmas, and a list of Catholic charities to donate to. According to Paul Clement, the former Bush administration solicitor general who argued on behalf of the church in the U.S. Court of Appeals for the D.C. Circuit at the end of March, that means the ad was really about“operating hours, tourist attractions, charitable giving, and Christmas.” It just happened to talk about those things from a religious perspective, rather than a commercial one. The WMATA policy, he argued, is discriminatory because it only “excludes advertisements that address those topics from a religious perspective.”

That’s a pretty cheeky argument, and one that would swallow up the entire viewpoint vs. subject matter distinction. Religious speech is always about more than just religion. Political speech is always about more than politics. By the church’s logic, if WMATA allowed a Chrysler ad, it would also have to allow a campaign ad calling for tighter fuel emissions, since both are “about” cars.

The church’s argument didn’t fare well at the federal district court level, where Judge Amy Berman Jackson wrote that “the Archdiocese’s proposed advertising campaign is not commentary about some other permissible topic — a topic other than religion — from a religious perspective; it is plainly a statement about religion from a religious perspective.” And it got a chilly reception from two of the three judges on the D.C. Circuit panel considering the church’s appeal, Judith W. Rogers and Robert L. Wilkins.

But the third judge, Brett Kavanaugh, a prominent conservative widely seen as a potential Republican Supreme Court nominee, was on board. “You’re saying you can wall off religion just like politics,” he said to WMATA’s lawyer, Donald B. Verrilli, Jr. — a solicitor general under Barack Obama. “The problem I have with that is the three cases saying you can’t separate religion as a subject matter from a religious viewpoint.”

He was right: three Supreme Court decisions do seem to support the church’s argument about religious speech. The cases — known as Lamb’s Chapel, Rosenberger, and Good News Club — were about whether a public school could deny the use of extracurricular resources to religious groups while making them available for other kinds of activities — like lectures, club meetings, and student publications — involving speech on public issues. Each time, the Court said the answer was no, categorizing it as viewpoint discrimination. In Lamb’s Chapel, for instance, the Court held that a group that wanted to screen a documentary advocating Christian family values had to be given the same access to school resources as any other group. (The lawyer who successfully argued that case, in 1993, was Jay Sekulow, now known as the lead attorney defending President Donald J. Trump in the Russia investigation.) “It discriminates on the basis of viewpoint,” the Court said, “to permit school property to be used for the presentation of all views about family issues and child rearing except those dealing with the subject matter from a religious standpoint.”

That’s the same reasoning that the D.C. archdiocese is using to justify running its ad on buses. And while there is something disingenuous about the claim that the “Perfect Gift” campaign was simply a message about operating hours from a religious perspective, the church has a point. It isn’t so easy to separate “viewpoint” from “subject matter.” At one moment during oral arguments, Judge Kavanaugh asked WMATA’s lawyer what would happen if the policy said, “No advertisements that promote or oppose Judaism.” Clearly, Judaism could be described as a subject matter. And yet a policy that outlaws discussions of Judaism, but not of other religions, looks blatantly like censorship of a particular viewpoint.

It’s easy to multiply the examples. Imagine a policy that allowed messages about family planning but not about the “topic” of birth control. Or one that allowed discussions of politics — but not the “topic” of socialism. There is no theoretically consistent way to police the difference between “viewpoint” and “topic.” It all depends on how broadly or narrowly we choose to define the subject matter at hand.

So there is an impasse. One landmark case, Lehman,says public transit doesn’t have to allow issue-based commentary just because it allows commercial advertisements. But another set of cases suggests the opposite: that there’s no way to rule out a subject matter without discriminating against a viewpoint.

This is now the most heated contest about the meaning of the First Amendment, at a time when many aspects of its meaning are intensely debated.

How do we make sense of this?

I did what I often do when my brain starts to buckle under the weight of a First Amendment puzzle: I called my old teacher, Robert Post, a professor at and former dean of Yale Law School who specializes in smoothing out the tangles of free-speech doctrine. When it comes to categorizing different types of speech, Post explained, the key is to stop focusing on the content of the speech and to think instead about how we characterize the speech act: not what the words say, but what they do. The government has to be able to discriminate — to apply different rules — based on the social context in which speech takes place. I can freely publish an op-ed arguing, falsely, that Pepsi cures cancer, but if Pepsi made the exact same claim in an advertisement, they could be taken to court.

That’s because the op-ed is taking place in the context of what Post calls “public discourse,” or speech that is closely relevant to shaping public opinion within our system of democratic self-government, so it gets the most stringent First Amendment protection. It gets that level of protection because, when it comes to forming public opinion, all speech is considered equal, in the sense of having an equal opportunity to persuade other citizens that it’s true or important. By contrast, the advertisement falls into the domain of “commercial speech.” In general, the government can regulate commercial speech — roughly, speech used in the conduct of business transactions and advertising — more freely, because it is generally less relevant to self-government than public discourse. Thus the government can compel tobacco companies to warn about the risks of cigarettes, but it can’t force a pro-smoking opinion columnist to do the same. It can ban false advertising but not false political statements.

The commercial/noncommercial speech framework isn’t perfect, but it helps resolve the public transit advertisement problem more coherently than the viewpoint/subject matter distinction. A cigarette ad and an anti-smoking billboard are both “about” cigarettes, but they aren’t the same type of speech act. Because commercial and noncommercial speech have different constitutional significance, it’s reasonable to let a public transit system draw a line between them.

Meanwhile, the reason the government screwed up in the religion-at-school cases is that religion and political speech should be on the same side of the line between commercial speech and public discourse — like it or not, religious questions are clearly relevant to issues affecting democratic self-government. By opening up a forum for discussion of issues but specifically excluding religion, the schools were discriminating based on the content of speech.

A policy like WMATA’s is defensible to the extent that it’s merely trying to allow commercial speech while keeping the system from becoming a forum for public discourse. (There is some evidence that it may need to do a better job policing that line: It allowed a Salvation Army campaign for charitable giving, which looks more like advocacy than commercial speech.) But the challenge to the policy comes at a moment when the Supreme Court’s conservative majority has grown increasingly skeptical of laws that treat commercial speech differently — and increasingly willing to strike down economic regulations on the grounds that they restrict speech. This is now the most heated contest about the meaning of the First Amendment, at a time when many aspects of its meaning are intensely debated.

Two of the three judges on the D.C. Circuit panel seem to favor WMATA’s argument, so the case may end there. But a ruling against WMATA, either at the circuit court or on appeal to the Supreme Court, could force the city to get out of selling ads entirely — or open its buses and trains to potentially inflammatory messages.

I wouldn’t really miss the ads; I have enough to look at outside my window. But a ruling that further weakened government’s ability to make distinctions between commercial speech and noncommercial speech, and regulate the former accordingly — now that would have consequences that ripple far beyond my local bus stop.